Blackboard eraser cleaner



Jan. 1, 1935. c A 1,985,939

BLACKBOARD ERASER CLEANER Filed April 14, 1932 PIEI. 1

31 INVENTOR.

IQQMJ M "2 14- ATTORNEY? UNITED STATES 1 Claim.

This invention relates to a portable cleaner for blackboard erasers. v

The chief object of this invention is to provide a cleaner that may be readily transported and which is a self contained unit and is particularly adapted for the cleaning of blackboard erasers. The chief feature of the invention is the construction of the unit whereby the chalk dust that the erasers pick up and hold is removed from the eraser and is collected in a bag which may be readily detached from the unit for cleaning or dumping. I j

The full nature of the invention will be under-' stood from the accompanying drawing and the following description and. claim: I

In the drawing, Fig. 1 is a top plan view of the unitary, portable eraser cleaner.

Fig. 2 is a side elevation thereof with part of the suction fan and housing structure shown in central and longitudinal section for showing the fan and the beater in elevation.

Fig 3 is a transverse sectional view taken on line 3-3 of Fig. 1 and in the direction of the arrows.

Fig. 4 is an enlarged sectional view of one portion of the beater and its supporting shaft, and is taken on the spiral section line 44 of Fig. 1 and in the direction of the arrows.

In the drawing, 10 indicates a base upon which is suitably mounted a motor 11 as at'12. The mothe circular plate portion 17 and the blade portions 18. The fan structure may be of any desired or preferred design. It is, however, suitably se cured to the portion.20.of the shaft of the motor which is extended and projects beyond the motor housing. The chamber 16 includes an outlet or discharge 21 which telescopically'supports a tube 22 that constitutes the mouth of a bag 23 adapted to receive the chalk dust. This bag, is of the usual type which will permit the air'to pass through the pores ofthe bag and whichpores will trap and hold the chalk dust. The sleeve 22 is suitably secured to the outlet 21 as by the clamping ring 24. V

Extending outwardly from the housing 14 is a chamber forming arrangement, orbeater housing, 25 providing the chamber 26 therein which PATENT. OFFICE 'John Cotton Mather, Indianapolis, Ind. V Application April 14, 1932, Serial No. 605,203

which are herein shown aligned and constitute the table upon which the eraser is supported. v Adjacent the junction ofthe housing 14 and the 7 table 29 is an abutment 30 which serves as a stop or guard protection for the hand of the per-'- son holding the eraser on the table.

Extending longitudinally through the chamber 26 is the extended portion 31 of the shaft and the same terminates as at 32 and in a bearing portion 33. A so-called dot type lubrication mechanism 34 is provided, whereby the bearing 33 may be occasionally oiled as required. Rigid with the shaft 31 there is mounted in the chamber 26 the beater construction. The beaterconstruction is herein shown comprised of a cylindrical body portion 35 and a pair of oppositely disposed wings 36 herein diametrically disposed. Each wing is spiraled with respect to the longitudinal axis of rotation. Each wing is progressively exposed through an opening 28 in the rotation of the beater by the shaft 31. clearly in Fig. 3 and as indicated by the numeral 37, each vane or blade of the beater is of greater depth intermediate the ends than at the ends. In other words, the high point of the beater blade occurs approximately midway between its ends, see Fig. 4.

The motor is of the-usual electrical type and may be what is known as a'single phase universal type and therefore, operable on alternating current or direct current.

20 1 As shown The, eraser is placed on the table with the handle up and the pad portion down and the eraser is moved to and fro across the table during the rotation of, the beater. The beaterin its rotation, taps the bottom of the eraser and loosens the chalk dust that has been taken up by the same. At the same time the fan is operating and, therefore, the fan sucks chalk .dust into the ably secured to the motor and in superposed'and spaced relation to the base and including an air inlet and an air discharge opening, a fan in said housing and mounted upon a portion of said extended shaft and rotatable therewith, a beater housing rigid with the fan housing and solely supported thereby in superposed and spaced rethe outlet 21 into the dust retain- T. lation to the base and including" at the remote end a shaft bearing for the free extended end of the shaft, said beater housing having an aperture therein and including a table formation ad- 5 jacent the aperture and a heater well having as an inlet said aperture and having an outlet communicating with the air inlet of the fan housing, and a bladed beater mounted in said well upon an intermediate portion of the extended shaft and arranged to project the vanes of said beater through the aperture for eraser engagement.

JOHN COTTON MATHER. 

